Martin Campbell is often described as a journeyman. I don't think it's an unfair thing for him to be called. He is a sturdy and reliable storyteller and a straightforward communicator of images and ideas.
How ironic is it then, that in a franchise defined partially by style (the women, the cars, the suits, the casinos, etc.) that the director who lacks an overt style of his own directed one of the best James Bond movies ever made? I’d argue that not only did he make one of the best Bond movies, but he also set a standard for blockbuster action movies in the 21st century.
And again, how unusual is it that, as the movies that followed Campbell's Casino Royale--specifically Skyfall, Spectre, and No Time To Do--became more visually lavish and ornate (some might even say fussed over) that they lost the X-factor that made Casino Royale special in the first place?
Casino Royale works because it tells a story grounded in character and reality. Campbell wasn't shooting for the moon. He wasn't trying to reinvent the wheel. If anything, he went in the opposite direction. He stripped Bond and the world around him down to the bone. In doing so, he excavated the core of the character and then polished it off for the 21st century.
It is precisely because Campbell avoided the excesses that became synonymous with the James Bond franchise that he succeeded in reinvigorating the character. It will never cease to amaze me how quickly the caretakers of the Bond franchise (and Daniel Craig himself) abandoned this approach in favor of affected villains with world domination plans, secret lairs, and a long embarrassingly sentimental emotional arc for the character.
From a certain vantage (indeed, many vantages) what comes after Casino Royale (and Quantum, which I quite like) sours the experience of watching it, because you know the mess that’s waiting around the corner. But looking at it another way, as I am inclined to do, the mess that started with Skyfall and ended with No Time To Die makes the rare gem that is Casino Royale shine all the brighter.